To have access to all the available versions, please follow this link.
The LHCb software is structured as a set of projects in Gitlab. The LHCb project contains general purpose classes used throughout the LHCb software. It is built on top of the Gaudi framework.
Normally, end users should not need to worry about selecting a version of LHCb, as this is selected automatically when selecting an application version. When working outside an application, the environment can be set using the lb-dev script (see the SoftwareEnvTools TWiki)
Documentation for available releases can be found by following the links at the top of this page.
A snapshot of the planned releases is always available in the LHCb nightly build system. See the SoftwareEnvTools TWiki for instructions on how to work against the nightlies.
Source code and binaries for supported platforms are available on disk (in cvmfs directory /cvmfs/lhcb.cern.ch/lib/lhcb - $LHCBRELEASES). The current list of supported platforms and compilers can be found in the LHCb TWiki pages
The source code of the tagged versions of LHCb can be browsed and downloaded from the gitlab tags tab. Click on the tag name then on the "browse files" icon. For project dependencies see the CMakeLists.txt file in the top level directory of the project.